A conventional injection valve for injecting highly pressurized fuel into the combustion chamber of an internal combustion engine, described in German Patent Application No. DE 101 06 168 A1, has an inlet connector used to introduce fuel into the interior of the injection valve, which connector can be placed into a corresponding connection socket of a fuel supply line. The inlet connector is sealed relative to the connection socket by a sealing assembly situated on the inlet connector. The fuel supply line standardly has a plurality of connection sockets via which fuel is distributed to a plurality of injection valves. The sealing assembly includes an intermediate or supporting ring fastened on the inlet connector, and two sealing rings realized as O-rings, seated above and below the intermediate or supporting ring on the inlet connector. The intermediate or supporting ring is preferably spray-molded onto the inlet connector, and is dimensioned such that a radial gap remains between its outer circumference and the inner wall of the connection socket. One of the sealing rings is situated below the intermediate or support ring, and one is situated above the intermediate or support ring. Due to the fuel pressure in the supply line and the connection socket, the upper sealing ring is pressed axially against the intermediate or support ring, and the lower sealing ring is pressed axially against a support shoulder that is fashioned on the side of the lower sealing ring oriented away from the intermediate or support ring, on the inlet connector, by a plastic extrusion molding. Here, both sealing rings seal radially against the inner wall of the connection socket.
It is also conventional to equip the sealing assembly with only one sealing ring, fashioned as an O-ring, and to situate the support ring between the sealing ring and support shoulder on the inlet connector. For reasons of assembly, the support ring is slotted, and, during installation of the inlet connector, is placed into the connection socket with its outer ring surface against the socket wall of the connection socket. In this way, a radial gap results between the inner ring surface of the support ring and the inlet connector.
It has turned out that the sealing ring pressed against the support ring under the pressure of the fuel is, over the long term, extruded into the radial gap between the support ring and the inlet connector on the one hand, and between the support ring and the connection socket on the other hand, and in this way is damaged over the long term to such an extent that its sealing function is impaired, or is completely lost.